$K_{e3}$ decay studies in OKA experiment
hep-ex
/ Authors
O. P. Yushchenko, V. F. Kurshetsov, A. P. Filin, S. A. Akimenko, A. V. Artamonov, A. M. Blik, V. V. Brekhovskikh, V. S. Burtovoy, S. V. Donskov, A. V. Inyakin
and 31 more authors
A. M. Gorin, G. V. Khaustov, S. A. Kholodenko, V. N. Kolosov, A. S. Konstantinov, V. M. Leontiev, V. A. Lishin, M. V. Medynsky, Yu. V. Mikhailov, V. F. Obraztsov, V. A. Polyakov, A. V. Popov, V. I. Romanovsky, V. I. Rykalin, A. S. Sadovsky, V. D. Samoilenko, V. K. Semenov, O. V. Stenyakin, O. G. Tchikilev, V. A. Uvarov, V. A. Duk, S. N. Filippov, E. V. Guschin
/ Abstract
Recent results from OKA setup concerning form factor studies in $K_{e3}$ decay are presented. About 5.25M events are selected for the analysis. The linear and quadratic slopes for the decay formfactor $f_{+}(t)$ are measured: $λ'_{+}=(26.1 \pm 0.35 \pm 0.28 )\times 10^{-3}$, $λ"_{+}=(1.91 \pm 0.19 \pm 0.14)\times 10^{-3}$. The scalar and tensor contributions are compatible with zero. Several alternative parametrizations are tried: the Pole fit parameter is found to be $M_V = 891 \pm 2.0$ MeV ; the parameter of the Dispersive parametrization is measured to be $Λ_+ =(24.58 \pm 0.18) \times 10^{-3}$. The presented results are considered as preliminary.